iTunes "smart encoding adjustments"

[chadbang]

Okay, I've scoured the web and can't find an answer. The MP3 encoder in itunes give you the normal options of bitrate, joint or normal stereo, etc. But there are two more options: "Filter frequencies below 10hz" - that' easy enough to figure out...
Then there's the option of "smart encoding adjustments". Anyone know what the hell this is? I can't find any explanation of what this option does. Very unusal on the web!

 

[blessingx]

Best I could find - http://docs.info.apple.com/article.html?artnum=31301 . Not much help.

 

[chadbang]

Thanks, Man. But, yeah, I'm still not exactly sure what apple means. Guess I'll just leave it checked.